/*
 * Copyright (C) 2012 Johan Boris Iantila jiantila@gmail.com && http://www.facebook.com/johanboris.iantila
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */



package mg.daloji.antandroyd;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.Collections;
import java.util.Map;
import java.util.WeakHashMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;


import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.util.Log;
import android.widget.ImageView;

public class ImageLoader {

	MemoryCache memoryCache=new MemoryCache();
	FileCache fileCache;
	private Map<ImageView, String> imageViews=Collections.synchronizedMap(new WeakHashMap<ImageView, String>());
	ExecutorService executorService; 
	final int stub_id = R.drawable.no_image;
	
	
	public ImageLoader(Context context){
		fileCache=new FileCache(context);
		executorService=Executors.newFixedThreadPool(5);
	}


	public void DisplayImage(String url, ImageView imageView){
	imageViews.put(imageView, url);
		Bitmap bitmap=memoryCache.get(url);
		if(bitmap!=null)
			imageView.setImageBitmap(bitmap);
		else{
			queuePhoto(url, imageView);
			imageView.setImageResource(stub_id);
		}
	}
	
	public void DisplayImageByResource(String trigramme, ImageView imageView){
	        if(trigramme.equals(CONSTANTS.RNM)){
	        	imageView.setImageResource(R.drawable.rnm);
	        }
	        if(trigramme.equalsIgnoreCase(CONSTANTS.ANTSIVA)){
	        	imageView.setImageResource(R.drawable.antsiva);
	        }
	        if(trigramme.equalsIgnoreCase(CONSTANTS.VIVA)){
	        	imageView.setImageResource(R.drawable.viva);
	        }
	        if(trigramme.equalsIgnoreCase(CONSTANTS.RDB)){
	        	imageView.setImageResource(R.drawable.rdb);
	        }
	        if(trigramme.equalsIgnoreCase(CONSTANTS.RDJ)){
	        	imageView.setImageResource(R.drawable.rdj);
	        }
	        if(trigramme.equalsIgnoreCase(CONSTANTS.ALLIANCE)){
	        	imageView.setImageResource(R.drawable.alliance1);
	        }

	        if(trigramme.equalsIgnoreCase(CONSTANTS.TARATRA)){
	        	imageView.setImageResource(R.drawable.taratra); 
	        }
	        if(trigramme.equals(CONSTANTS.RVM)){
	        	imageView.setImageResource(R.drawable.rvm); 
	        }
	}
	
	
	public Bitmap DisplayImage(String url){
		Bitmap bitmap=memoryCache.get(url);
		return bitmap;
	}

	private void queuePhoto(String url, ImageView imageView){
		PhotoToLoad p=new PhotoToLoad(url, imageView);
		executorService.submit(new PhotosLoader(p));
	}

	private Bitmap getBitmap(String url) 
	{
		File f=fileCache.getFile(url);

		//from SD cache
		Bitmap b = decodeFile(f);
		if(b!=null)
			return b;

		//from web
		try {
			Bitmap bitmap=null;
			URL imageUrl = new URL(url);
			HttpURLConnection conn = (HttpURLConnection)imageUrl.openConnection();
			conn.setConnectTimeout(30000);
			conn.setReadTimeout(30000);
			conn.setInstanceFollowRedirects(true);
			InputStream is=conn.getInputStream();
			OutputStream os = new FileOutputStream(f);
			Utils.CopyStream(is, os);
			os.close();
			bitmap = decodeFile(f);
			return bitmap;
		} catch (Exception ex){
			ex.printStackTrace();
			return null;
		}
	}

	//decodes image and scales it to reduce memory consumption
	private Bitmap decodeFile(File f){
		try {
			//decode image size
			BitmapFactory.Options o = new BitmapFactory.Options();
			o.inJustDecodeBounds = true;
			BitmapFactory.decodeStream(new FileInputStream(f),null,o);

			//Find the correct scale value. It should be the power of 2.
			final int REQUIRED_SIZE=70;
			int width_tmp=o.outWidth, height_tmp=o.outHeight;
			int scale=1;
			while(true){
				if(width_tmp/2<REQUIRED_SIZE || height_tmp/2<REQUIRED_SIZE)
					break;
				width_tmp/=2;
				height_tmp/=2;
				scale*=2;
			}

			//decode with inSampleSize
			BitmapFactory.Options o2 = new BitmapFactory.Options();
			o2.inSampleSize=scale;
			return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
		} catch (FileNotFoundException e) {}
		return null;
	}

	//Task for the queue
	private class PhotoToLoad
	{
		public String url;
		public ImageView imageView;
		public PhotoToLoad(String u, ImageView i){
			url=u; 
			imageView=i;
		}
	}

	class PhotosLoader implements Runnable {
		PhotoToLoad photoToLoad;
		PhotosLoader(PhotoToLoad photoToLoad){
			this.photoToLoad=photoToLoad;
		}

		@Override
		public void run() {
			if(imageViewReused(photoToLoad))
				return;
			Bitmap bmp=getBitmap(photoToLoad.url);
			memoryCache.put(photoToLoad.url, bmp);
			if(imageViewReused(photoToLoad))
				return;
			BitmapDisplayer bd=new BitmapDisplayer(bmp, photoToLoad);
			Activity a=(Activity)photoToLoad.imageView.getContext();
			a.runOnUiThread(bd);
		}
	}

	boolean imageViewReused(PhotoToLoad photoToLoad){
		String tag=imageViews.get(photoToLoad.imageView);
		if(tag==null || !tag.equals(photoToLoad.url))
			return true;
		return false;
	}

	//Used to display bitmap in the UI thread
	class BitmapDisplayer implements Runnable
	{
		Bitmap bitmap;
		PhotoToLoad photoToLoad;
		public BitmapDisplayer(Bitmap b, PhotoToLoad p){bitmap=b;photoToLoad=p;}
		public void run()
		{
			if(imageViewReused(photoToLoad))
				return;
			if(bitmap!=null)
				photoToLoad.imageView.setImageBitmap(bitmap);
			else
				photoToLoad.imageView.setImageResource(stub_id);
		}
	}

	public void clearCache() {
		memoryCache.clear();
		fileCache.clear();
	}

}
